[PATCH V3 2/3] ARM: clk-gate2: Add API imx_clk_gate2_exclusive for clk_gate2

Shengjiu Wang
2014-08-11T02:56:42Z

On Sat, Aug 09, 2014 at 09:33:17PM +0800, Shawn Guo wrote:
> On Fri, Aug 08, 2014 at 03:02:48PM +0800, Shengjiu Wang wrote:
> > As some clocks are mutually exlcusive, they can't be enabled simultaneously,
> > So add this new API for registering exclusive clock, the enable function will
> > check if there is exclusive clock and it is not enabled, then this clock can
> > be enabled, otherwise, it will return error.
> >
> > Signed-off-by: Shengjiu Wang <shengjiu.wang@freescale.com>
> > ---
> > arch/arm/mach-imx/clk-gate2.c | 18 +++++++++++++++++-
> > arch/arm/mach-imx/clk.h | 2 ++
> > 2 files changed, 19 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/arm/mach-imx/clk-gate2.c b/arch/arm/mach-imx/clk-gate2.c
> > index 84acdfd..df64c4d 100644
> > --- a/arch/arm/mach-imx/clk-gate2.c
> > +++ b/arch/arm/mach-imx/clk-gate2.c
> > @@ -8,7 +8,7 @@
> > *
> > * Gated clock implementation
> > */
> > -
> > +#include <linux/clk-private.h>
>
> I do not see why this header is needed.
>
> Shawn
>
I add new function imx_clk_gate2_exclusive(), which need to access "struct clk_hw"
in "struct clk", So here need include clk-private.h

> > #include <linux/clk-provider.h>
> > #include <linux/module.h>
> > #include <linux/slab.h>
> > @@ -34,6 +34,7 @@ struct clk_gate2 {
> > u8 flags;
> > spinlock_t *lock;
> > unsigned int *share_count;
> > + struct clk *clk_exclusive;
> > };
> >
> > #define to_clk_gate2(_hw) container_of(_hw, struct clk_gate2, hw)
> > @@ -46,6 +47,11 @@ static int clk_gate2_enable(struct clk_hw *hw)
> >
> > spin_lock_irqsave(gate->lock, flags);
> >
> > + if (gate->clk_exclusive && __clk_is_enabled(gate->clk_exclusive)) {
> > + spin_unlock_irqrestore(gate->lock, flags);
> > + return -EBUSY;
> > + }
> > +
> > if (gate->share_count && (*gate->share_count)++ > 0)
> > goto out;
> >
> > @@ -147,3 +153,13 @@ struct clk *clk_register_gate2(struct device *dev, const char *name,
> >
> > return clk;
> > }
> > +
> > +int imx_clk_gate2_exclusive(struct clk *clk1, struct clk *clk2)
> > +{
> > + struct clk_gate2 *gate1 = to_clk_gate2(clk1->hw);
> > + struct clk_gate2 *gate2 = to_clk_gate2(clk2->hw);
> > +
> > + gate1->clk_exclusive = clk2;
> > + gate2->clk_exclusive = clk1;
> > + return 0;
> > +}
> > diff --git a/arch/arm/mach-imx/clk.h b/arch/arm/mach-imx/clk.h
> > index d5ba76f..2b07376 100644
> > --- a/arch/arm/mach-imx/clk.h
> > +++ b/arch/arm/mach-imx/clk.h
> > @@ -36,6 +36,8 @@ struct clk *clk_register_gate2(struct device *dev, const char *name,
> > struct clk * imx_obtain_fixed_clock(
> > const char *name, unsigned long rate);
> >
> > +int imx_clk_gate2_exclusive(struct clk *clk1, struct clk *clk2);
> > +
> > static inline struct clk *imx_clk_gate2(const char *name, const char *parent,
> > void __iomem *reg, u8 shift)
> > {
> > --
> > 1.7.9.5
> >